Tag: M.W=100-200

Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 56423-63-3, name is 2-Bromopyrazine, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of 2-Bromopyrazine

General procedure: Method S Parallel preparation of Examples 39-40: To a set of vials containing the requisite aryl bromide (0.12 mmol) was added bis[(tetrabutylammonium iodide)copper(I) iodide] (3.9 mg, 0.0034 mmol), 1,10 phenanthroline (2.5 mg, 0.014 mmol) followed by Cs2C03 (68 mg, 0.21 mmol). The vials were capped and transferred into a glove box under an atmosphere of nitrogen. To each vial was added a solution of H2 (30 mg, 0.069 mmol) in dioxane (1.0 mL). The vials were capped and the mixtures were heated at 100 C with stirring overnight. After that time, the mixtures were allowed to cool to RT. To each vial was added water (2 mL) and DCM (2 mL). The mixtures were transferred to a set of fritted barrel filters. The organic layer from each mixture was drained into a clean vial. Additional DCM (1 mL) was added to each aqueous layer and the organic layer was again drained and combined with the previous organic extract. The solvent from the combined organic layers was removed in vacuo. The crude residues were dissolved in DMSO (1 mL) and filtered. The crude products were purified by mass triggered reverse phase HPLC using the following conditions: [column: Waters XBridge CI 8, 5muiotaeta, 19×100 mm; solvent gradient: 19-21% initial to 49-51% final MeCN (0.1% NH4OH) in water (0.1% NH4OH) 25 mL/min; 8 min run time] to afford Examples 39-40.

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 56423-63-3.

Reference:
Patent; MERCK SHARP & DOHME CORP.; DAI, Xing; CUMMING, Jared, N.; LIU, Hong; SCOTT, Jack, D.; (0 pag.)WO2016/85780; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, This compound has unique chemical properties. The synthetic route is as follows., Product Details of 109838-85-9

Step 1: Synthesis of Intermediate 1-4.1R8 (212 g, 1151 mmol) in tetrahydrofuran (dry) (600 mL) is cooled to -78°C. Then n-butyllithium(2.5 M in hexanes, 552 mL, 1381 mmol) is added dropwise, keeping the temperature below -78°C.After 30 mm R9 (324g, 1209 mmol) in tertahydrofuran (dry) (120 mL) is added dropwise. Thereaction mixture is stirred at -78°C for 1 h. The mixture is quenched with saturated NH4C1 solutionand extracted three times with ethyl acetate. The organic layer is washed with brine, dried overNa2SO4 and evaporated in vacuo. The residue is purified by flash chromatography (heptane/ ethyl acetate = 80/20). Yield 60percent.

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 109838-85-9.

Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; ANDERSKEWITZ, Ralf; GRAUERT, Matthias; GRUNDL, Marc; OOST, Thorsten; PAUTSCH, Alexander; PETERS, Stefan; WO2014/140091; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 68774-77-6, name is 8-Chloro[1,2,4]triazolo[4,3-a]pyrazine, belongs to pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 68774-77-6, Safety of 8-Chloro[1,2,4]triazolo[4,3-a]pyrazine

A mixture of crude 4-methylbenzyl 4-(aminomethyl)-3,3-difluoropiperidine-1-carboxylate (600mg, 2.0 mmol), 8-chloro-[1,2,4]triazolo[4,3-a]pyrazine (360 mg, 2.0 mmol) and DIPEA (0.76 mL, 4.0 mmol) in butyl alcohol (10 mL) was heated at 130 C overnight. The mixture was allowed to cool to room temperature and concentrated under reduced pressure. The concentrate was purified by column chromatography over silica gel (100% ethyl acetate) to afford the title compound as a light gray powder (150 mg, 18%). MS (ESI) calcd for C20H22F2N602: 416.2; found: 417.3 [M+H]. 1H NMR (400MHz, CD3OD) 6 9.16 (s, 1H), 7.77 (d, J = 4.8 Hz, 1H), 7.29 (d, J = 4.8 Hz, 1H), 7.24 (d, J = 8.0 Hz, 2H), 7.17 (d, J = 8.0 Hz, 2H), 5.09 (s, 2H), 4.33 (br s, 1H), 4.19-4.15 (m, 1H), 4.05-3.95 (m, 1H), 3.72-3.58 (m, 1H), 3.25-2.90 (m, 2H), 2.67-2.51 (m,1H), 2.33 (s, 3H), 1.99-1.93 (m, 1H), 1.62-1.52 (m, 1H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 8-Chloro[1,2,4]triazolo[4,3-a]pyrazine, and friends who are interested can also refer to it.

Reference:
Patent; RUGEN HOLDINGS (CAYMAN) LIMITED; SHAPIRO, Gideon; (246 pag.)WO2016/196513; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 88625-24-5, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 88625-24-5 name is 5-Chloropyrazine-2-carbaldehyde, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

2) N,N-dimethylformamide (10 mL) was added to 5-chloropyrazine-2-carbaldehyde (500 mg), methyl 2,2-dimethyl-3-{[4-methyl-5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan- 2-yl)pyridin-2-yl]oxy}propanoate (1410 mg) and 2N aqueous sodium carbonate solution (5.26 mL), and after replacing the atmosphere with nitrogen, palladium chloride (dppf) methylene chloride complex (143 mg) was added to the mixture and the resulting mixture was stirred at 65C for 2 hours. To the reaction mixture were added ethyl acetate and water, and the liquids were separated. After filtration with Celite, the organic layer was separated, washed with water and then with a saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (n-hexane: ethyl acetate=100:0 to 70:30) to obtain methyl 3-{[5-(5-formylpyrazin-2-yl)-4-methylpyridin- 2-yl]oxy}-2,2-dimethylpropanoate (855 mg). MS (m/z): 330 [M+H]+

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 5-Chloropyrazine-2-carbaldehyde, and friends who are interested can also refer to it.

Reference:
Patent; MITSUBISHI TANABE PHARMA CORPORATION; SAKURAI, Osamu; SARUTA, Kunio; HAYASHI, Norimitsu; GOI, Takashi; MOROKUMA, Kenji; TSUJISHIMA, Hidekazu; SAWAMOTO, Hiroaki; SHITAMA, Hiroaki; IMASHIRO, Ritsuo; WO2012/81736; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 33332-28-4,Some common heterocyclic compound, 33332-28-4, name is 2-Amino-6-chloropyrazine, molecular formula is C4H4ClN3, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

[0504] Compound 481A was prepared by an analogous method as that of 473B, except using compound 2-chloro-6-aminopyrazine in place of compound 2-bromo-6-aminopyridine.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Amino-6-chloropyrazine, its application will become more common.

Reference:
Patent; Das, Jagabandhu; Padmanabha, Ramesh; Chen, Ping; Norris, Derek J.; Doweyko, Arthur M.P.; Barrish, Joel C.; Wityak, John; Lombardo, Louis J.; Lee, Francis Y.F.; US2004/54186; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 54608-52-5, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 54608-52-5 as follows.

Ethyl 1-benzyl-2,4-dioxopiperidine-3-carboxylate (58.5 mg, 0.21 mmol) in EtOH (2 mL) was added to a biotage microwave vial under nitrogen containing 2-hydrazinopyrazine (38.5 mg, 0.35 mmol) at RT. To this stirred reaction mixture was added AcOH (0.024 mL, 0.42 mmol) and then stirred at RT for 18 hours in a sealed microwave vial. The reaction was heated to 140 C for 10 hours in the microwave reactor and cooled to RT. The reaction mixture was evaporated in the Genevac and then redissolved in 2 ml DMSO, filtered and the crude product was purified by flash RP chromatography (35g Puriflash, 15mu, HC column), using decreasingly polar mixtures of water (containing 1% NH4OH) and MeCN as eluents. Fractions containing the desired compound were evaporated to dryness to afford 5-benzyl-2-(pyrazin-2-yl)-1,2,6,7-tetrahydro-3H-pyrazolo[4,3-c]pyridine-3,4(5H)-dione (14.6 mg, 19.2 %) as a white solid.

According to the analysis of related databases, 54608-52-5, the application of this compound in the production field has become more and more popular.

Reference:
Article; Fairley, Gary; Greenwood, Ryan; McMillan, Caroline Anne; Tetrahedron Letters; vol. 59; 39; (2018); p. 3574 – 3578;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 109838-85-9, These common heterocyclic compound, 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

(S)-((2S,5R)-5-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazin-2-yl)(4-(trifluoromethyl)phenyl)methanol: To a mixture of (R)-2,5-dihydro-3,6-dimethoxy-2- isopropylpyrazine (5.2 tnL, 29 mmol)(commercially available from 3B Scientific Corporation Product List (Order Number 3B3-054672)) and THF (50 mL) at -78°C was added n-butyllithium (2.5 M solution in hexane, 12 mL, 31 mmol). The mixture was stirred for 15 minutes. The colorless solution turned light brown. A solution of 4- (trifluoromethyl)benzaldehyde (5.1 mL, 38 mmol)(commerciaHy available from 3B Scientific Corporation Product List (Order Number 3B4-3644)) in THF (50 mL) was added dropwise through a dropping funnel at -78°C. The mixture was stirred for 1 hour. The reaction mixture was diluted with EtOAc and washed with a mixed solution of aqueous Na2HPO4 and KH2PO4 solution (pH =8). The aqueous layer was extracted with EtOAc three times. The combined organic layers were washed with water and brine, dried over Na2SO4, and concentrated in vacuo. The crude residue was separated into two isomers by silica gel chromatography: 0-2percent- 10percent CH3CN-CH2CI2. The product was obtained as light yellow oil (2.3 g, 22 percent). LCMS (API-ES) m/z: 359 (M+H*).

The synthetic route of 109838-85-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AMGEN INC.; WO2009/11871; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 16298-03-6, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 16298-03-6 as follows.

Step 1a: Methyl 3-[(2,4-dimethoxybenzyl)amino]pyrazine-2-carboxylate Sodium triacetoxyborohydride (7.82 g, 36.89 mmol) was added to a mixture of methyl 3-aminopyrazine-2-carboxylate (4.00 g, 26.12 mmol) and 2,4-dimethoxybenzaldehyde (4.83 g, 29.04 mmol) in 1,2-dichloroethane (90 ml). The reaction was continued at room temperature for 24 hours. Sodium triacetoxyborohydride (13.0 g, 61.34 mmol) and 2,4-dimethoxybenzaldehyde (8.0 g, 48.14 mmol) were added and the reaction continued at room temperature over night. Water and DCM were added and the phases separated. The product was purified further by flash chromatography (SiO2, heptane:ethyl acetate, product came at 50percent ethyl acetate) and recrystallisation (DCM/heptane) to give a slightly yellow solid (5.00 g, 63percent). 1H NMR (400 MHz, CDCl3) delta 8.35-8.27 (br, 1H), 8.22 (d, 1H), 7.82 (d, 1H), 7.20 (d, 1H), 6.48-6.43 (m, 1H), 6.43-6.37 (m, 1H), 4.63 (d, 2H), 3.93 (s, 3H), 3.84 (s, 3H), 3.77 (s, 3H). MS m/z 304 (M+H)+.

According to the analysis of related databases, 16298-03-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Cheng, Leifeng; Jonforsen, Maria; Schell, Peter; US2009/88439; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 356783-15-8, name is 3,6-Dichloropyrazine-2-carboxylic acid, A new synthetic method of this compound is introduced below., Recommanded Product: 3,6-Dichloropyrazine-2-carboxylic acid

(b) In 2.0 mL of methylene chloride was suspended 0.2 g of 3,6-dichloro-2-pyrazinecarboxylic acid. Then, 0.001 mL of N,N-dimethylformamide and 0.14 mL of oxalyl chloride were successively added at an ice-cooled temperature, and the mixture thus formed was stirred at room temperature for 40 minutes. The reaction mixture was concentrated to dryness under reduced pressure and then dissolved in 3.0 mL of acetonitrile. Then, 0.3 g of potassium fluoride and 0.056 g of 18-crown-6-ether were added and the mixture thus formed was stirred at 60 C. for 2.5 hours in an atmosphere of nitrogen gas. The reaction mixture was poured into 3.0 mL of methanol, the insoluble matter was filtered off, and then the filtrate was concentrated to dryness under reduced pressure. The residue was purified by silica gel chromatography [eluent: n-hexane:ethyl acetate-9:1] to obtain 0.15 g of methyl 3,6-difluoro-2-pyrazinecarboxylate as a colorless oily product.

The synthetic route of 356783-15-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Toyama Chemical Co., Ltd.; US2003/130213; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 6863-73-6, name is 3-Chloropyrazin-2-amine, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Recommanded Product: 6863-73-6

8-Chloroimidazor 1 ,2-alpyrazine[00237] 2-Bromo-l,l-diethoxyethane (6.21 mL, 0.041 mmol) was added to a mixture of 48% HBr (aq.) solution (1.64 mL) and water (20 mL) and the resulting mixture was stirred under reflux for 1 hour. The reaction mixture was then allowed to cool and washed with brine (2 x 30 mL), dried (MgSO4) and carefully concentrated in vacuo. The resulting oil was dissolved in 1 ,2-dimethoxoethane (20 mL) and added to a suspension of 2-amino-3 -chloro- pyrazine (2.142 g, 0.016 mmol) in 1 ,2-dimethoxoethane (30 mL). 48 % HBr (aq.) solution (0.313 mL) was then added and the resulting mixture was stirred under reflux for 1 hour. Upon cooling a precipitate formed which was collected by filtration and washed with diethyl ether to give the crude HBr salt. This was dissolved in NaHCO3 (aq.) and extracted into DCM. Drying of the organic layer (MgSO4) followed by concentration in vacuo provided the title compound (1.9 g, 75%) as a yellow/pale brown solid. 1H NMR (d6-DMSO): 8.68-8.64 (IH, br m), 8.30-8.26 (IH, br m), 7.88-7.85 (IH, br m), 7.75-7.70 (IH, br m).

The synthetic route of 3-Chloropyrazin-2-amine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BioMarin IGA, Ltd.; WREN, Stephen Paul; WYNNE, Graham Michael; LECCI, Cristina; WILSON, Francis Xavier; PRICE, Paul Damien; MIDDLETON, Penny; WO2010/69684; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem